Boring machine



July 12, 1966 D. B. ROTTLER 3,260,136

BORING MACHINE Filed May 27, 1963 5 Sheets-Sheet 1 FlG so [I 29 & 1 a .JIi 26 Q J a n) I I07 I 24 I20 ffglfi I IM M ||4 J I l 20 DONALD B.ROTTLER INVENTOR.

AS11 Ex ATTORNEYS Filled May 1963 TLER BORING FIG 2 4 I 94 Bo H as \l 677 I 940 78 a 74 I J W E I L lo as i in!!! DONALD ROTTLER N VEN TO BYQSMQ'B ATTORNEYS July 12, 1966 B, ROTTLER 3,260,136

BORING MACHINE Flled May 27, 1963 5 Sheets-Sheet 5 30 I l 3? m 38 W 3|340 7% I FlG 6 DONALD B. OTTLER INVENTOR.

QWQ E AT TORNEYS TLE BORING MACHINE Filed May 1963 5 Sheets-Sheet 4 FIG|4 FIG ATTORNEYS y 2, 1966 D. B. ROTTLER 3,260,136

BORING MACHINE Filed May 27, 1965 5 Sheets-Sheet 5 DONALD B. ROTTLERINVENTOR.

ATTORNEYS United States Patent 3,260,136 BORING MACHINE Donald B.Rottler, 1221 Poplar Place, Seattle, Wash. Filed May 27, 1963, Ser. No.283,446 3 Claims. (Cl. 774) The present invention relates to an improvedverticalspindle boring machine particularly adapted for the 'boring ofengine cylinders and is of the type in which the work piece is clampedon a stationary bed and the boring unit is moved on the bed to boringposition and then is clamped thereto.

By an large the original manufacturers of automotive engines use the panrails of the engine block as a clamping surface to locate the mainbearings and the cylinders. One of the principal objects of the presentinvention is to provide a boring machine 'by which the pan rails canalso be conveniently used as the reference during the reboring operationto insure that the rebored cylinders will be parallel to one another andperpendicular to the crank shaft. A related object is to provide afixture for conveniently handling Y-blocks and V-blocks and properlyorientating their pan rails with respect to the boring machine.

Another important object of the invention is to provide an improvedboring bar assembly having centering fingers below the cutter which canbe easily retracted from above and the cutter used without need of firstwithdrawing the boring bar.

The invention further aims to provide an improved boring bar of thevertical cantilevered type having dampening means preventing chatteringor undue vibration from action of the cutter.

Still other objects are to provide an air support whereby the boringunit can -be easily moved and adjusted at will on the stationary bed,and to provide an improved power clamping arrangement for selectivelyclamping the boring unit to the bed and maintaining a continuous equalclamping pressure.

Other more particular objects and advantages of the invention will, withthe foregoing, appear and be understood in the course of the followingdescription and claims, the invention consisting in the novelconstruction and in the adaptation and combination of parts hereinafterdescribed and claimed.

In the accompanying drawings:

FIG. 1 is a perspective view of a boring machine embodying the presentinvention.

FIG. 2 is an enlarged fragmentary transverse vertical sectional viewtaken generally as indicated by line 22 of FIG. 1.

FIG. 3 is a horizontal sectional view taken along the line 3-3 of FIG.2.

FIG. 4 is a fragmentary longitudinal vertical sectional view taken asindicated by line 44 of FIG. 2.

FIG. 5 is a detail view of the lifting groove shown in smaller scale inFIG. 2.

FIG. 6 is an enlarged fragmentary vertical sectional view takengenerally as indicated by line 6-6 in FIG. 1 and with the centeringfingers expanded.

FIG. 7 is a detail vertical sectional view taken on line '7-7 of FIG.10.

FIGS. 8, 9 and are horizontal sectional views taken along the lines 88,99 and 1010, respectively, of FIG. 6.

FIG. 11 is an enlarged view partly in vertical section of one of theengine block clamping devices.

FIG. 12 is a detail horizontal sectional view taken as indicated by line1212 of FIG. 11.

FIGS. 13 and 14 are schematic views illustrating the function of theindexing bar.

3,26,136 Patented July 12, 1966 FIG. 15 is an end view of myengine-block fixture.

FIG. 16 is a detail vertical sectional view taken along the line 1616 ofFIG. 15.

FIG. 17 is a fragmentary perspective view illustrating the positioningof a spacer on the pallet of the fixture for use with V-blocks; and

FIG. 18 is a perspective view of pallets for use with in-line engineblocks.

Referring to the drawings it is seen that the boring machine of thepresent invention has a stationary bed 20 having an upper planar slidesurface 21 which is laterally offset above a table having a pair of wearpads 22 for receiving an engine-block fixture 23. The slide 21 has alongitudinal keyway 24 of inverted-T cross-section for receivingmatching anchoring keys 25 depending from a pair of clamping units 2626which are provided to lock the engine block relative to the bed 20. Alsooccupying the keyway 24 is an elongated locking key 27 suspended from aboring unit 28 which is adjustable both lengthwise and laterally on theslideway 21. The base housing 29 for the boring unit presents a reach 30overlying the table 22 for guiding an upright sleeve 31 which is keyedtherein for vertical sliding movement. This sleeve 31 is fixedlysurmounted by a driving head 32 containing mechanism for selectivelytransferring power from the upper end of an upright screw 33, located tothe rear of the sleeve, to the upper end of a boring bar 34 which isjournaled in the sleeve and extends there- 'beyond both top and bottom.The housing 29 carries a motor 35 and contains drive mechanism fortransfer of power from this motor to the lower end of the screw 33. Feedmechanism is located in the head 32 for selectively moving the head,sleeve and boring bar vertically relative to the work.

Directing attention to FIGS. 6-10 the sleeve 31 is accurately journaledrelative to the housing 29 at the ends of the reach 30 as by taperedbushings 37 which are held in anular end caps 38 by screw rings 40. Feltsealing washers 41 held by retainers 42 may be provided. The sleeve 31has suitable bearings for the boring bar 34 including an internallytapered thrust bushing 43 at the bottom which is provided with a seal 40and is mated to a tapered bar portion 34a which joins a base crown 34b.Mounted on the latter is a boring head 45 containing a holder 46 for acutter 47 and having a bottom cavity 48 for receiving and centering adisc-like counterweight 50. The cavity 48 is closed by a two-piece case51 which holds upper and lower pairs 5353 and 5454, respectively, ofcentering fingers with the upper fingers at right angles relative to thelower fingers.

It will be noted that the boring bar 34 is tubular to receive a coaxialshaft 55 for operating the centering fingers. This shaft 55 projectsabove the head 32 to receive a manual adjusting knob 56 and at its lowerend has a fitting 57 which is splined to a stub shaft 58. The latterdepends freely through the center of a cross-wall 60 in the boring head45, and through the counterweight 50, and the end walls of the case 51to receive upper and lower pinions 61-62. These pinions are located injoining center cavities 63-64 formed in the two halves 51a51b of thecase 51 and mesh with racks formed on the opposed faces of the shanks ofthe centering fingers so that the fingers 53-53 mesh at diametricallyopposite points on the pinion 61 while the fingers 5454 mesh in likemanner with the pinion 62. To accommodate and guide the centeringfingers, respective pairs of chordal grooves 53a and 54a are providedwhich intersect the center cavities 6364.

Three anchoring screws 65 extend through the two halves of the case 51,the counterweight 50, and the boring head 45 into the base crown 34b ofthe boring bar.

However, it is important to note that the three openings 50a in thecounterweight for the screws 65 are purposely larger in diameter thanthe screws so that the counterweight is free to oscillate about itscenter relative to boring head 45. The maximum angular amount of thismovement is closely controlled by a sleeve 69 on one of the screws 65 asshown in FIG. 7. This sleeve is press-fitted in the upper wall of thefinger case 51 and is smaller by a preset small amount in externaldiameter than the diameter of the related hole 50a in the counterweight50. The resulting limited angular oscillation of the counterweightrelative to the boring head dampens and eliminates objectionablevibration and chattering which would otherwise arise from action of thecutter 47 during the boring operation.

As shown in FIGS. 6 and 8 the boring head 45 also has a round uppercavity 66 which is intersected by a radial slot 66a for passage of theholder 46. The cutter 47 is received in an endwise bore in the holder 46and is locked therein by a set screw 67 while the holder in turn is heldby a transverse set screw 68. At its inner end the holder seats againstan indexing screw 70 and engages a leaf spring '71 on the under side.This spring is housed in an upwardly exposed slot 72 formed in the wall60 at a slight cross-angle relative to the holder 46, and it will benoted that the slot 72 has a step 72:: at its end portion remote fromthe set screw 70 on which the root end of the spring 71 rests so thatthe cantilevered end of the spring can flex downwardly. Thiscantilevered end has a double tapered lug 71a on its upper side whichcooperates with a like shaped transverse groove 46a formed in ahorizontally narrowed tail portion 46b of the holder to resist outwardendwise movement of the holder while being set. The tip of the tail 46bis beveled top and bottom and on the side facing oppositely from the setscrew 68 and the resulting point is engaged by the indexing screw 70.With this arrangement the cutter can be very finely adjusted by use ofthe screw 70 and the adjustment held by the spring 71 until the screw 68is tightened. The setting of the screw 70 is held by a lock screw 73.

Viewing FIGS. 2-4, the base of the housing 29 for the boring unit 28 hasa slot '74 therethrough traversing the keyway 24 in the top surface 21of the bed 20'. Riding in the slot 7 2- and surmounting the locking key27 is a block 75 through which a pull bolt 76 passes from the lockingkey. This pull bolt has a lock nut 77 bearing on the top of the block 7and the latter has a set screw 78. At its upper end the pull bolt 76passes through a slot 80 in a lever plate 81 to receive a head nut 82which bears against the rim 80a of the slot. The lever plate 81 ispivoted at its rear end by fulcrum dowels 82 on the top of a back stubwall 83 and has top diverging side ribs 81a which gradually verticallythicken to the front of the lever plate and have a pair of lateral ears84. These ears bear against the top of a pair of lever arms 85 which arefulcrumed on an intermediate stub wall 86 and extend rearwardly to makepin connections 87 with the piston rods 88 of a pair of pneumaticlifting cylinder units 90 which are anchored to the base of the housing29. Since the ears 84 are adjacent the front fulcrum ends of the leverarms 85 the force exerted by the hydraulic cylinders 90 on the rear endsof the lever arms is multiplied several times to the forward end of thelever plate 81. This force is further multiplied by the lever plate onthe nut 82 of the pull bolt '76 and results in a concentrated forcebeing exerted by the locking key 27 against the upper shoulders 24a ofthe keyway 24-. In this manner selective loading of the lifting cylinderunits 90 firmly locks the boring unit 28 to the bed 20 at the desiredposition.

The ends of the upright leg of the T-shaped locking key 27 are cut backto accommodate a pair of sleeve rollers 81 which are journaled onstepped pins 92 upstanding from the base of the key. These rollerscontact the side walls of the upper necked portion of the keyway 24 foraiding ease of movement of the boring unit 28 lengthwise of the keywaywhen the lifting cylinders are deactivated. Such ease of movement isaided materially by providing compressed air lifting. To accomplish thisa shallow groove 93 (FIG. 5) preferably closed at its ends, is formedalong the underside of the housing 29 in parallel relation to the keyway24 and approximately directly beneath the center of balance of theboring unit 28. This groove 93 has a supply port 93a and is selectivelyprovided with high pressure air through a line 94 connecting to the portby a fitting 940. When the groove 93 is charged with compressed air theresulting lift exerted on the boring unit makes it easy to move itmanually along the keyway 24 or transverse thereto. In the latterinstance the lever plate 81 moves relative to the pull bolt 76 by way ofthe slot 80, the lever plate being held by the fulcrum dowels 82.Continuing to the fixture 23, such is for use with V- blocks orY-blocks, and therefore its pallet is formed with a pair of longitudinalrails 100a-100a and 100b 1000 which are at right angles to one another.A pair of of end blocks 101 surmount the ends of the pallet, each havinga pair of mounting feet 101a bolted at 102 to the rails 100a. At theirupper edge the end blocks 101 have a pair of centered rectangularcutouts 103 arranged to receive a mating indexing bar 104 with itslongitudinal edges parallel to the pallet surfaces 100a, 10% and 1000.These cutouts 103 are closed at the top by head plates 105 bolted at 106to the end blocks. It will be noted that each of the head plates jutsoutwardly and has a vertical bore 105a with a bottom counter-bore 105bto receive a threaded clamping rod 107 having a nut 108 pinned at itslower end. The upper face of each of these nuts 108 has multiple radialgrooves 108a to interfit with a dowel 110 depending from the floor ofthe related counter-bore 105a to prevent rotation of the respectiveclamping rod 107. Each of the rods 107 also has a pair of jam nuts111-112 which are spaced sufliciently above the respective bottom nut108 to permit the rods 101 to be tilted from the vertical when not undertension so that their upper ends can be swung into and out of end slots118a in the web of a holddown bar 113 of channel stock. This bar isclamped by a pair of wing nuts 114 on the rods 107.

Preparatory to mounting an engine block on the pallet, the pallet isplaced in a suitable cradle to hold it such that the pallet rails aregenerally horizontal. Then before clamping the engine block against thepallet rails 100a it is properly positioned with respect to the palletby use of the indexing bar 104 as illustrated in FIGS. 13-14 whereinnumeral 115 indicates one of the main bearings of the engine block. Withthe engine block generally centered on the pallet the indexing bar isthreaded through the end openings 103 of the pallet and the main bearingopenings. Then the engine block is shifted laterally until the rims ofall of the bearings engage an upper chamfered edge, 104a of the indexingbar. When this is accomplished the hold-down bar 113 is clamped inposition. In this manner parallelism between the cylinder banks of theclamped engine block and the pallet base surfaces 100b-100c is insured.

When Y-blocks are mounted on the fixture 23 their pan rails are seateddirectly on the rails 100a of the pallet 100. However when V-blocks aremounted a spacer 116 is used between the pan rails and the pallet rails.As shown in FIG. 17 this spacer has locating pins 117 for lateralcentering and is positioned between the end blocks 101. It also hasupper cutouts 118 registering with the cutouts 103 for receiving the bar104.

The hold-down bar 113 is provided with a lifting eye 120 so that thepalleted engine block can be conveniently hoisted onto the bed 20 with aselected one of the pallet base surfaces 100!) and 1000 seated on thewear plates 22 and the block alined parallel to the keyway 24. Then theengine block is clamped relative to the bed 20 by use of the clampingunits 26.

The key 25 of each of the clamping units is fixed at the lower end of aclamping screw 121 which extends upwardly through a cantilevering beam122 having a machined bottom surface portion 12211 for seating againstthe top of the bed 20. To button down the beam, pressure is manuallyapplied by use of a handled nut 123 having a lock nut 124. A verticalboss 125 is formed at the forward reaching end of the beam 122 toslidably receive a sleeve 126 having a front foot 127. The base 125 hasa horizontal front bore 125b partially intersecting the vertical bore125a for the sleeve 126. Slidable in this front bore 125]) are a pair ofopposed wedges 128- 129 comprising cylinders with beveled wedging faces1286l-129d. Wedge 128 is threaded on a lightening screw 130 passingthrough the front bore 125k and having a manual turning knob 131 at oneend. The other wedge 129 is sleeved on the screw 130 and bears by itslarger end against a stop shoulder 130a. With this arrangement turningof the knob 131 draws the wedging faces 128a-- 129a against the sleeve126 and locks it against endwise movement relative to the beam 122.

Slidable within the sleeve 126 is a rod 132 having a pivot ring 133pinned at its lower end. At its upper end the rod has a forked cam 134straddling a fiat-sided neck portion 132a at the top of the rod andpivoted thereon by a pin 135. The cam 134 is operated by a handle 136which when pulled down, causes the cam to bear against a washer 137 andpull up on the rod 132. This causes the ring 133 to draw on the heel ofa clamping foot 138 having a counter-bore in which the ring is seated,and this action in turn downwardly pivots the toe of the foot about aninverted fulcrum bolt 140. This bolt has its head received in a bottomcounter-bore in the clamping foot and passes upwardly at a slope throughan oversized bore adjacent the outer end of the sleeve foot 127. Jamnuts 141 retain the bolt 140 while permitting the required play betweenthe feet 127 and 138.

In using the clamping units 26 the sleeves 132 are initially set so thatthe heels of the feet 138 are at approximately the level of the top ofthe engine block to be secured on the bed. Then it is only necessary topull down on the handles 136 to perfect the clamping action.

Reviewing the operation of the boring machine, the engine block to berebored is clamped on one of the fixtures 23 and is lifted onto the wearplates 22. Then, after the fixture is lined up the engine block isclamped to the bed by the clamps 26. An air valve (not shown) is thenopened to supply compressed air to the groove 93 exerting a lift on theboring unit 28 which can then be easily'moved to position the boringhead over the first cylinder. Following this the boring head is loweredinto the cylinder bore and the two pairs of centering fingers 53-53 and54-54 are expanded by turning the knob 56. Final adjustment is then madeon the boring unit 28 relative to the bed 20 to obtain bore contact byall of the centering fingers. The air supply to the groove 93 is thenshut off and an air valve (not shown) is opened to supply the cylinders90-90 to power clamp the boring unit 28 against the bed 20. After thecentering fingers have been retracted by use of the knob 56, the machineis ready for commencement of the reboring operation. After one bank ofcylinders has been rebored the clamps 26 are released, the fixture 23 isturned ninety degrees to move from one of the base fa-ces 100b-100c tothe other, and the operation is repeated on the other bank. The boringmachine of the present invention is not limited for use in reboringY-block or V-block engines. For in-line engines a pair of L-shapedpallets 142 (FIG. 18) are used between the engine block and the wearplates 22.

And, of course, the boring machine of the present invention can be usedfor many other machining purposes than the reboring of engine cylinders.

It is believed that the invention will have been clearly understood fromthe foregoing detailed description of my now-preferred illustratedembodiments. Changes in the details of construction maybe resorted towithout departing from the spirit of the invention and it is accordinglymy intention that no limitations be implied and that the hereto annexedclaims be given the broadest interpretation to which the employedlanguage fairly admits.

What I claim is:

1. In combination, a cantilevered boring bar with a boring head at itsouter end having a cutter holder and presenting a round socket with itsmouth at the outer end of the head, a centering finger assembly closingsaid mouth and located closer to the outer end of the head than saidholder, a counter-weight disc in said socket, means for limiting turningmovement of said counterweight relative to said socket, and meansextending through said boring bar, head, counter-weight, and into saidassembly for operating the latter.

2. The structure of claim 1 in which said means for limiting turningmovement of said counter-weight includes the shank of a screw extendingthrough said assembly, counter-weight, and head into the outer end ofthe boring bar for securing said assembly and head to the boring bar.

3. In combination, a boring bar with a boring head, said head having around socket centered with respect to the longitudinal center axis ofsaid bar, a round counterweight turnable in said socket and having anoff-center hole therethrough, and means extending through said hole intosaid head and smaller than said hole for permitting limited angularoscillation of said counter-weight with respect to said axis.

References Cited by the Examiner UNITED STATES PATENTS 1,220,399 3/1917Cowell 77-2 1,436,669 11/1922 Ness 77-2 1,520,382 12/1924 Workman.

1,980,975 11/1934 Beck 77-2 2,040,273 5/1936 Rottler 77-5 8 2,051,9548/1936 Leland 77-58 2,198,135 4/1940 Strasburg et al. 74-574 2,420,7595/ 1947 Stelz 77-4 2,45 8,995 1/ 1949 Hummer.

2,486,813 11/1949 Yount 77-4 2,714,823 8/ 1955 Dall et al.

2,834,233 5/ 1958 Anderson 77-2 2,903,916 9/1959 Carlstedt 77-32,904,287 9/ 1959 Ertsgaard et al. 248-25 2,904,288 9/ 1959 Krauss etal. 248-25 3,053,119 9/1962 Anderson 77-4 3,106,110 10/ 1963 Senn 77-4FOREIGN PATENTS 1,222,770 6/1960 France.

WILLIAM W. DYER, JR., Primary Examiner. DONALD R. SCHRAN, Examiner. G.A. DOST, Assistant Examiner.

1. IN COMBINATION, A CANTILEVERED BORING BAR WITH A BORING HEAD AT ITSOUTER HAVING A CUTTER HOLDER AND PRESENTING A ROUND SOCKET WITH ITSMOUTH AT THE OUTER END OF THE HEAD, A CENTERING FINGER ASSEMBLY CLOAINGSAID MOUTH AND LOCATED CLOSER TO THE OUTER END OF THE HEAD THAN SAIDHOLDER, A COUNTER-WEIGHT DISC IN SAID SOCKET, MEANS FOR LIMITING TURNINGMOVEMENT OF SAID COUNTERWEIGHT RELATIVE TO SAID SOCKET, AND MEANSEXTENDING THROUGH SAID BORING BAR, HEAD, COUNTER-WEIGHT, AND INTO SAIDASSEMBLY FOR OPERATING THE LATTER.